In math, at lower levels, we're taught that you can't divide by zero. If you are taught that division is repeated subtraction, then it can be explained that the reason you can't divide by zero is because there is no defined, fixed number of zeros you can subtract out of any given number (you can always subtract one more zero out of any given number, you see). Therefore, the result of division by zero is undefined. Then, if you pursue math into calculus, you find out you can divide by zero... sorta... through the limit process, by using numbers that are as close to zero as you care to get without being exactly zero.
And, again, we learn in school algebra something called "the order of operations." It's the order in which we perform competing tasks given in a problem. There's a nifty mnemonic called PEMDAS which stands for Parentheses, Exponents, Multiplication, Division, Addition, Subtraction, reminding us that when we have multiple operations to perform, then we must do them in that order.
And, if we pursue math further, we find out "the order of operations" is no such thing; the deeper explanation is that, for logical coherence and uniformity of results, certain operators have precedence over others, and with this understanding we can work problems in whatever fashion we like so long as we honor the order of operator precedence.
So it is with the law of God. We might think of the "arithmetic" level of the commandments is the "thou shalt nots." The "algebra" level is the "thou shalts," and the "calculus" level of the law is this: every last thing you wish people would do to you, do to others. That is the Golden Rule, and it is the entirety of the law; all the other commandments are merely implications of this law.
All of this is a setup to say that just as calculus may seem, to the grade schooler, to contradict what he understands of math, so also might Jesus's conduct seem to contradict the commandments he gave, and for the same reason. Jesus comprehended the totality of the law, and, analogously, was teaching arithmetic to those who did not understand the law, algebra to those who did understand, while he himself was practicing calculus. Calculus gets taught to the diligent and self-motivated student who loves the subject for its own sake.
The requests Jesus did not fulfill were those which break the Golden Rule, or those in which God had a contrary commandment in place. "Lord, take my side and impose my will upon another!" No. "Lord, give me that which I cannot understand will destroy me!" No. "Make God jump through hoops for you!" No. "Save yourself!" No.
The most interesting one was where he granted the legion of demons their request, but declined to grant the newly-freed man his wish to follow him. Christ had a mission to minister to all Israel, and the knee-jerk reaction of the people of that city to this deed was fear - of him! They were so afraid they begged him to leave. To fulfill his mission to them, which God had given, Jesus asked the man to stay as a witness to his power and glory among them, that after their initial fear had left them, they might, if they wished, find Jesus. And the man did so.
If, therefore, you meant it when you witnessed to God that you were willing to keep Jesus's commandments, then go and give to everyone that asks - and perform every other commandment Jesus gave - that you also may understand the law, and comprehend the problems that it solves.